Moscow - Russian President Vladimir Putin said Thursday Donald Trump had made "significant achievements" as US leader, rejecting claims that Moscow meddled in the election that brought the American president to power.

Putin was speaking in a wide-ranging annual press conference that also touched on Olympic doping and Arctic exploration.

The marathon event, which has in the past lasted up to almost five hours and this year saw more than 1 600 journalists accredited, was Putin's first major public appearance since announcing he would seek a new six-year term in March 2018 elections.

"We can see several quite significant achievements in the short time he has been at work," Putin said when asked to assess Trump's time in power.

"Look at how the markets are reacting, they are growing. This shows confidence in the American economy. With all due respect to (Trump's) opponents, these are objective facts," he said.

But he said that accusations Moscow had interfered in last year's US presidential election to swing the result had been "made up" by US opposition to discredit Trump's work in the White House.

He referred to contact between Trump's team and representatives of the Russian government, which he said was normal diplomatic practice.

"What is so transgressive in this case and why should it take on this spy-thriller tone?" Putin asked.

Call for political competition

The press conference kicked off with a question from a Moscow radio station on why Putin was seeking re-election.

"To improve quality of life for Russians," said Putin, who has been in power since 1999. He could become the country's longest-serving leader since Joseph Stalin if he wins a fourth term.

Putin said he would stand for election as an independent candidate rather than with the backing of his traditional party, United Russia.

A journalist asked about the state of the opposition in polls in which Putin will face only nominal competition and is all but certain to cruise to victory.

According to a survey published by independent pollster Levada on Wednesday, 75 percent of Russians would be prepared to vote for Putin in March, despite having yet to hear any specific campaign pledges.

"Is it up to me to form the opposition myself?" Putin replied. "I think in politics, as in the economy, there should be competition. I will strive for this."

One of these opponents is Ksenia Sobchak, a former socialite turned liberal TV presenter who many suspect is running as a Kremlin "spoiler" candidate to split the opposition and boost interest in the polls.

Sobchak, whose father was Putin's political mentor and who is rumoured to be the president's goddaughter, was at Thursday's event as a journalist for opposition television channel Dozhd. She was expected to be allowed to ask a question.

Putin's main challenge will be to convince Russians to vote at all in an election that he is widely expected to win. According to Levada, only 28 percent of Russians said they were certain to vote in March.

Carnival atmosphere

Putin also addressed the doping scandal that has seen Russia barred from competing in next year's Winter Olympics and athletes from the country only allowed to take part under a neutral flag.

He said he hoped Russia could work "constructively" with the World Anti-Doping Agency and the International Olympic Committee, which banned the country over state-sponsored doping.

But Russia would "defend the interests of our athletes, including in civil courts," he said.

Putin acknowledged that doping violations took place but claimed that the scandal was politically motivated.

The president typically addresses the economy at the annual event.

On Thursday he said it was "obvious" the Russian economy was growing and reported "brilliant" grain exports, while highlighting Arctic exploration and mineral extraction as a priority.

As in previous years, there was a carnival atmosphere in the press conference hall. Journalists held signs to attract the president's attention and one reporter even dressed as the Russian equivalent of Father Christmas, an AFP correspondent said.

Signs offered an indication of the sort of question the reporters would ask if given the floor by the president. Slogans included "children," "agriculture," "Krasnoyarsk is choking," and "spiritual foundations".